// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.

#ifndef STORAGE_LEVELDB_UTIL_TESTUTIL_H_
#define STORAGE_LEVELDB_UTIL_TESTUTIL_H_

#include "gmock/gmock.h"
#include "gtest/gtest.h"
#include "helpers/memenv/memenv.h"
#include "leveldb/env.h"
#include "leveldb/slice.h"
#include "util/random.h"

namespace leveldb
{
    namespace test
    {

        MATCHER(IsOK, "") { return arg.ok(); }

// Macros for testing the results of functions that return leveldb::Status or
// absl::StatusOr<T> (for any type T).
#define EXPECT_LEVELDB_OK(expression) \
    EXPECT_THAT(expression, leveldb::test::IsOK())
#define ASSERT_LEVELDB_OK(expression) \
    ASSERT_THAT(expression, leveldb::test::IsOK())

        // Returns the random seed used at the start of the current test run.
        inline int RandomSeed()
        {
            return testing::UnitTest::GetInstance()->random_seed();
        }

        // Store in *dst a random string of length "len" and return a Slice that
        // references the generated data.
        Slice RandomString(Random *rnd, int len, std::string *dst);

        // Return a random key with the specified length that may contain interesting
        // characters (e.g. \x00, \xff, etc.).
        std::string RandomKey(Random *rnd, int len);

        // Store in *dst a string of length "len" that will compress to
        // "N*compressed_fraction" bytes and return a Slice that references
        // the generated data.
        Slice CompressibleString(Random *rnd, double compressed_fraction, size_t len,
                                 std::string *dst);

        // A wrapper that allows injection of errors.
        class ErrorEnv : public EnvWrapper
        {
        public:
            bool writable_file_error_;
            int num_writable_file_errors_;

            ErrorEnv()
                : EnvWrapper(NewMemEnv(Env::Default())),
                  writable_file_error_(false),
                  num_writable_file_errors_(0) {}
            ~ErrorEnv() override { delete target(); }

            Status NewWritableFile(const std::string &fname,
                                   WritableFile **result) override
            {
                if (writable_file_error_)
                {
                    ++num_writable_file_errors_;
                    *result = nullptr;
                    return Status::IOError(fname, "fake error");
                }
                return target()->NewWritableFile(fname, result);
            }

            Status NewAppendableFile(const std::string &fname,
                                     WritableFile **result) override
            {
                if (writable_file_error_)
                {
                    ++num_writable_file_errors_;
                    *result = nullptr;
                    return Status::IOError(fname, "fake error");
                }
                return target()->NewAppendableFile(fname, result);
            }
        };

    } // namespace test
} // namespace leveldb

#endif // STORAGE_LEVELDB_UTIL_TESTUTIL_H_
